Process for dyeing keratinous material with ortho-diphenols



nited Sttes PROCESS FOR DYEI NG KERATINOUS MATERIAL 'WITHORTHO-DIPHENOLS This invention relates to the dyeing of hair and otherkeratinous substances.

It is already known to dye hair by means of oxidation dyes, that is tosay, compounds which give coloured derivatives only on oxidation. bymeans of a reactant such as hydrogen peroxide. There may be mentionedamong these oxidation dyes aromatic polyamines, aminophenols and certainpolyphenols, including triphenols, such as pyrogallol,hydroxyhydroquinone and. its nuclear substitution derivatives. However,it is to be noted that the development of the shade in the dyeing bymeans of these oxidation dyes isgenerally effected: in alkaline mediumand that the shade obtained is: generally not the final shade, but thatit changes slowly and reaches this final shade only after 24 hours orevenmore. Moreover, the shades obtained arenot always sufiiciently deepand this disadvantage is overcome by mordanting by means of metallicsalts. Unfortunately, such a mordanting treatment makes it substantiallyimpossible to proceed to subsequent treatments such as, for example,permanent waving by means of mercaptans or bleaching by means ofhydrogen peroxide or persalts.

The present invention provides a process for dyeing live hair and otherkeratinous substances by means of solutions of o-diphenols. The processis readily performed, at room temperature, avoids the aforesaiddisadvantages and achieves the final desired shade very rapidly, thecoloration being fast to light, rubbing and shampooing.

According to the present invention a process of dyeing hair or otherkeratinous substance comprises applying thereto an aqueous or aqueousalcoholic solution of at least one ortho-diphenol having the followinggeneral formula:

in which R represents a hydrogen orhalogen atom or an aldehyde, alkyl,.cycloalkyl, aralkyl, carboxy, carboxyalkyl, alkoxy, nitroalkyl ornitrohydroxyalkyl. group or an amino acid residue, and developing. theshade by means of one or more inorganic oxidizing agents selected fromammonium or alkali metal iodates, periodates and persulphates.

Where the group R is other than hydrogen, the position of the nuclearcarbon atom to which the group R is attached may differ in accordancewith the isomers which can be actually obtained, but this carbon atom ispreferably that in 4-position. v

Ortho-diphenols of the above-defined type include notably, in additionto pyrocatechol (l), the following compounds: homopyrocat'e'chol (2),protocat'ec'huic acid (3),

'protocatechu-al'dehyde 4), 4-bromopyrocatecho1 (5' 4-methoxypyrdcatechol (6'), 3-4-dihydroxy-beta-phenylalanine (7),alpha-(3-4-dihydroxyphenyl) beta nitroethanol (8), but this enumerationcannot be regarded as any limitation of the invention.

The choice of the o-diphenol, or of the respective proportions of thevarious o-diphenols of the mixture which may be employed, dependsprincipally, though not exclusively, upon the final shade desired. Thecombined concentration of the o-diphenol or o-diphenols in the aqueousor aqueous alcoholic solution may be comprised Within a fairly widerange depending upon the desired shade. It will preferably be betweenabout 0.01 mole and 1 mole of o-di'pheno'l per litre of solution.

The pH-value of the solutions which may be employed for. carrying outthe process according to the invention may vary within a very widerange, e.g. between about 1 and 11. Together with the choice of theparticular 0- diphenol or o-dip'henols used, the pH-value permits tocontrol the final shade. Since the invention is not limited to theproduction of any particular shade, the pH-value at which the process iscarried out is not a feature of the invention. Nevertheless it will beunderstood that, so far as hair-dyeing is concerned. the pH-value shouldnot be such that the solution employed will irritate the scalp or impairthe essential properties of the hair, such as its chemical structure,its elasticity and its mechanical strength. In. the case (referred tolater herein) where the solution to be applied to hair contains any ofthe aforesaid oxidizing agents, the optimum choice of the pH-value isalso dependent on the nature of this oxidizing agent.

The invention further includes the products of the process of theinvention, such as human hair (not on the head) or other forms offhair,felts, furs, feathers and keratinous products generally.

The dyeing process according to the invention may be carried out invarious ways. According to a preferred embodiment of the invention, anaqueous or aqueousalcoholic solution of the o-diphenol or o-diphenols isprepared, to which solution the inorganic oxidizing agent or agentsspecified are added at the time of application to the hair. The pH ofthis solution may be adjusted to a neutral, acid or alkaline value bythe addition of suitable reactants or the solution may be used as such,that is to say, without any component other than the o-diphenols and theoxidizing agents, the pH-value of the solution depending only on therespective proportions of each of these two types of components.Whatever the pI-I-value at which the operation is carried out, thesolution is left in contact with the hair e.g. for five to 60 minutes,thoroughly rinsed with water, shampooed, rinsed again and dried.

In this preferred method of carrying out. the process, the inorganicoxidizing agent or agents may be introduced into the o-di'phenolsolution, either in the form of powder or in aqueous solution.

According to another embodiment of the invention, the operation isperformed in two steps by first applying the solution of the o-diphenolor o-diphenols, free from any oxidizing agent, leaving this solution incontact with the hair e.g. for 5 to 60 minutes, in order to complete theimpregnation, gently blotting oh the excess of liquid, optionally afterrinsing with water, and then applying to the hair an aqueous solution ofthe oxidizing agent, and leaving it in contact with the hair fortheperiod necessary for the development of the shade, generally from 5to 20 minutes, the hair then being rinsed, shampooed', rinsed again anddried.

It will be appreciated that the foregoing process, though described inrelation to hair, may be applied to alternative keratinous materials.The second embodiment of the invention described above may be modifiedin various ways; it is possible to use an oxidizing solution, thepH-value of which is neutral, acid or alkaline,

said pH-value being irrespective of that of the o-diphenol solutionapplied in the first stage. If it is desired to develop the shade inacid medium, the oxidizing solution may be acidified by means of anorganic or inorganic acid or by means of any suitable acid buffer.However, if an alkali metal or ammonium iodate or periodate is used, itis preferable not to reduce the pH below 3 and not to use stronginorganic acids for obtaining the lowpH values. Reversely, if it isdesired to de'velop the shade in a basic medium, the oxidizing solutionmay be made alkaline bymeans of any suitable alkaline reagent, forexample by means of ammonia, an amine, or an ammonium or alkali metalcarbonate or phosphate.

'Whatever the pH-value chosen for the development of the shade andshould the process be carried out in one or two stages, theconcentration of the oxidizing agent in the solution containing it maybe varied between wide limits depending. upon the shade to be obtainedand do pending upon the solubility of the oxidizing agents used.Generally speaking, the quantity of oxidizing agent to be employedcorresponds to about 0.5 to 10 grams per 100 cc. of the o-diphenolsolution employed, whether this solution contains or does not containthe oxidizing agent, the volumes of o-diphenol solution and/ or ofoxidizing agent to be employed being determined by the bulk of hair orby the quantity of other keratinous product to be dyed.

Instead of using aqueous or aqueous alcoholic solutions as aforesaid thereactants may be applied in the form of creams, pastes or jellies, theadjustment to the required consistency being effected by any means usualin hair dyeing.

The following examples will serve to illustrate the in vention.

Example I A solution having the following composition is prepared:

Grams Pyrocatechol 2 Acetic acid 0.5

Water to make 100 cc;

time.

Example I] A solution having the following composition is prepared:

Grams Pyrocatechol 3 Acetic a 0.5

Water to make 100 cc.

At the time when this solution is applied to naturally White live hair,there is added thereto 5 grams of potassium periodate. After 20 minutescontact (pH=4), the hair is rinsed with water, shampooed, rinsed againand dried. A beautiful grey-black shade is obtained.

Example Ill The following solution is prepared:

Grams 4-methoxy-pyrocatechol 2 Lactic acid 0.5 Water to make 100 cc.

Immediately before application to live white hair, 1 gram of sodiumiodate is added. The solution is left in contact with the hair for 20minutes, and the hair is thereafter rinsed, shampooed, rinsed again anddried. A

beautiful auburn shade is obtained.

4 Example IV on live white hair.

' Example V A solution having the following composition is prepared:

Grams Beta-(3,4-dihydroxyphenyD-(1) alanine 2 Acetic acid 0.5

Water to make cc.

Immediately before this'solution is applied to live, naturally whitehair, 1, gram of sodium iodate is added thereto. The solution is left incontact with the hair for 20 minutes, and the hair isthereafter rinsed,shampooed, rinsed again and dried. I

The hair is dyed a beautiful grey-black.

r Example VI The following solution is prepared:

. Grams Protocatechu-aldehyde 2 Ethyl alcohol 20 Acetic acid 0.5

Water to make 100 cc.

- i Grams 4-bromopyrocatechol 2 Acetic acid 0.5

Water to make 100 cc.

. At the time of use, 5 grams of sodium iodate is added to thissolution, which is left in contact with the hair for 15 minutes,whereafter, the hair is rinsed, shampooed, rinsed again and dried. Alight brown shade having a red tinge is obtained.

' If the sodium iodate is replacedby an equal weight of potassiumperiodate, a substantially identical shade is obtained.

Example VIII The following solution is'prepared:

Grams Pyrocatechol 2 20% ammonia so1ution 1.2

Water to make 100 cc.

Shortly before application to the hair, 5 grams of powdered sodiumiodate areadded to this solution. The pH-value of the mixture is 9.4.'After 20 minutes contact with the hair, the latter is rinsed,shampooed, rinsed again and dried. A light brown shade is therebyobtained on naturally white live hair.

Immediately before the hair is impregnated therewith, 5 grams ofpowdered sodium persulphate is added -to this solution, which is left incontact with the hair for 15 minutes (pH=4.8), whereafter the hair i srinsed,

shampooed, rinsed again and dried. A dark blond shade is obtained onwhite or near-white live hair.

Example X 1 gram of sodium iodate is introduced into a solution havingthe following composition:

Grams 4-methoxy-pyrocatechol 2 20% ammonia solution 1.2 Water to make100 cc.

After contact for 20 minutes, the hair is rinsed, shampooed, rinsedagain. and dried. On greying. hair, a light chestnut having a greenishtinge is thus obtained.

Example Xl The following solution is prepared:

' Grams Protocatechu-aldehyde a- 2 20% ammonia solution 1.2

Water to make 100 cc.

At the time of application to naturally white live hair, Sgrams ofsodium iodate is added to this solution. After contact for 20 minuteswith the hair, the latter is rinsed, shampooed, rinsed again and dried.A light blond shade is thus obtained.

Example XII A solution having the following composition is prepared:

. Grams 4-bromopyrocatechol .t... 2 20% ammonia 1 ,1.2

Water to make 100 cc.

Before this solution is applied to the hair, 5 grams of sodium iodate isadded thereto. It is. left in contact with the-hair for 15 minutes,whereafter the hairis rinsed, shampooed, rinsed again and dried. A lightchestnut colour is thereby obtained.

Example XIII A. solution having the following composition is prepared:

Gram

Pyrocatechol 1 Water to make 100 cc.

Live grey hair is impregnated with this solution. After contact forminutes, the. excess of liquid is blotted off, for example by means of atowel, and a 4% by weight aqueous sodium iodate solution (pH=5) is thenapplied. This solution is left in contact with the hair for minutes, andthe hair is then rinsed, shampooed, rinsed again and dried. The hair isdyed a light blond verging on mahogany.

Example XIV A solution having the following composition is applied tonearly white live hair:

Grams Pyrocatechol 4 Acetic acid 0.5'

Water to make 100 cc.

After contact for 10 minutes and gentle blotting, a 4% by weight aqueoussodium iodate solution is applied to the hair. This solution is left in.contact with the hair for 1 0 minutes, Whereafter the hair is rinsed,shampooed, rinsed again and dried. A light mahogany shade is obtained. 71 Example X V The following solution is prepared:

Grams 4-brornopyrocatechol 2 Acetic acid 0.5

Water to make 100 cc.

Example X VI Naturally white live hair is impregnated with the followingsolution:

Grams Pyrocatechol l 20% ammonia solution 1.2

Water to make cc.

The solutionis left in contact with the hair for 10 minutes and the hairis then gently blotted. The following composition is then applied:

Grams Sodium io 4 20% ammonia solution 1.2 Water to make 100 cc.

After a period of 10 minutes, the hair is rinsed, shampooed, rinsedagain and dried; A blond shade with a slight violet tinge is obtained.

Example VII A solution having the following composition is prepared:

Grams Pyrocatechol 3 Sodium tartrate 7 Tartaric acid 5.2

Water to make 100 cc.v

The pH-value of this solution is 3.1. 7.2 grams of sodiumpersulphate'are added to this solution, which is immediately applied tonaturally white live hair. After 5 minutes, the pH-value of the solutionclose to the cortex of the hair is 2.8. After a total impregnation timeof 25 minutes, the hair is briefly rinsed, shampooed,

rinsed again and dried. 'The shade obtained is a very light blond.

Example XVIII The following'solution is prepared:

Grams Pyrocatechol 3 Acetic acid 1 Water to make 100 cc.

The pH-value of the solution. is 2.8. At the time of the application ofthe solution to live, naturally white hair, 2 grams of sodium iodate areadded. The solution is left in contact with the hair for 15 minutes,during which it is observed that the pH-value of the part of thesolution close to the hair does not vary. The hair is then brieflyrinsed, shampooed, rinsed again and dried. The shade thus obtained isash-chestnut.

Example XIX The following composition is prepared:

Grams Pyrocateehol 6 Sulphonated higher fatty alcohol 3 Water to make100 cc.

The pH-value of this mixture is 4. 4 grams of sodium iodate are added tothis composition which is immediately applied to naturally white livehair. After contact for 15 minutes, during which it is observed that thepH of the solution close to the hair does not vary, the hair is rinsedwith tapwater and dried. An ash-chestnut shade is obtained.

If, in this example, the sodium iodate is replaced by '1. A process fordyeing hair and other keratinous ma terials which comprises applyingthereto an aqueous solution consisting of at least one orthodiphenol ofthe general formula:

wherein R is selected from the class consisting of the hydrogen atom,the halogen atom, aldehyde, alkyl, carboxy, alkoxy, nitro-hydroxyalkyland alpha amino propanoic groups, and an oxidizing agent selected fromthe class consisting of ammonium and alkali metal iodates, periodatesand persulphates.

2. A process for dyeing hair and other keratinous materials whichcomprises applying thereto an aqueous solution consisting, in the globalproportion of 0.1 to 1.0 mole per litre, of at least one orthodiphenolof the general formula:

wherein R is selected from the class consisting of the hydrogen atom,the halogen atom, aldehyde, alkyl, carboxy, alkoxy, nitro-hydroxyalkyland alpha amino propanoic groups, said solution also containing afreshly added oxidizing agent selected from the class consisting ofammonium and alkali metal iodates, periodates and persulphates, thequantity of oxidizing agent being 0.5 to grams per litre of saidorthodiphenol solution.

3. A process for dyeing hair'- and other keratinous materials whichcomprises applying thereto an aqueous solution consisting, in the globalproportion of 0.1 to 1.0 mole per litre, of at least one orthodiphenolof the general formula:

wherein R is selected from the class consisting of the hydrogen atom,the halogen atom, aldehyde, alkyl, carboxy, alkoxy, nitro-hydroxyalkyland alpha amino propanoic groups and thereafter applying thereto anoxidizing agent selected from the class consisting of ammonium andalkali metal iodates, periodates and persulphates, the quantity ofoxidizing agent being 0.5 to 10 grams per litre of said orthodiphenolsolution.

4. A process for dyeing hair and other keratinous materials whichcomprises applying thereto an aqueous solution consisting, in the globalproportion of 0.1 to 1.0

mole per litre, of at least eral formula:

wherein R is selected from the class consisting of the hydrogen atom,the halogen atom, aldehyde, alkyl, carboxy, alkoxy, nitro-hydroxyalkyland alpha amino propanoic groupsand thereafter applying thereto asolution of an oxidizing agent selected from the class consisting ofammonium and alkali metal iodates, periodates and persulphates, thequantity of oxidizing agent being 0.5 to 10 grams per litre of saidorthodiphenol solution, and allowing said oxidizing solution to remainin contact with the hair for 5.20 minutes. i

5. A process for dyeing hair and other keratinous materials whichcomprises applying thereto an aqueous solution of pH 3 to 11 consisting,in the global proportion of 0.1 to 1.0 mole per litre, of at least oneorthodiphenol of the general formula:

wherein R is selected from the class consisting of the hydrogen atom,the halogen atom, aldehyde, alkyl, carboxy, alkoxy, nitro-hydroxyalkyland alpha amino propanoic groups, said solution also containing afreshly added oxidizing agent selected from the class consisting ofammonium and alkali metal iodates, periodates and persulphates, thequantity of oxidizing agent being 0.5 to 10 grams per litre of saidorthodiphenol solution.

6. A process for dyeing hair and other keratinous materials whichcomprises aplying thereto an aqueous solution of pH 3 to 11 consisting,in the global proportion of 0.1 to 1.0 mole per litre, of at least oneorthodiphenol of the general formula:

wherein R is selected from the class consisting of the hydrogen atom,the halogen atom, aldehyde, alkyl, carboxy, alkoxy, nitro-hydroxyalkyland alpha amino propanoic groups and thereafter applying thereto anaqueous References Cited in the file of this patent UNITED STATESPATENTS 2,539,202 Peck Ian. 23, 1951 FOREIGN PATENTS 745,144 GreatBritain Feb. 22, 1956 OTHER REFERENCES Kass: Am. Perf. and Aromatics,August 1956, pp. 34-37.

Kass: Am. Perf. and Aromatics, September 1956, pp. 47-50.

one orthodiphenol of the gen-

1. A PROCESS FOR DYEING HAIR AND OTHER KERATINOUS MATERIALS WHICHCOMPRISES APPLYING THERETO AN AQUEOUS SOLUTION CONSISTING OF AT LEASTONE ORTHODIPHENOL OF THE GENERAL FORMULA: